I. Field
The following description relates to wireless communications, in general, and to interference management in unplanned wireless communication systems, in particular.
II. Background
Wireless communication systems are widely deployed to provide various types of communication. For instance, voice and/or data can be provided via such wireless communication systems. A typical wireless communication system, or network, can provide multiple users access to one or more shared resources (e.g., bandwidth, transmit power). For instance, a system can use a variety of multiple access techniques such as Frequency Division Multiplexing (FDM), Time Division Multiplexing (TDM), Code Division Multiplexing (CDM), Orthogonal Frequency Division Multiplexing (OFDM), and others.
Generally, wireless multiple access communication systems can simultaneously support communication for multiple user equipment (UEs). Each UE can communicate with one or more base stations (BSs) via transmissions on forward and reverse links. The forward link (or downlink (DL)) refers to the communication link from BSs to UEs, and the reverse link (or uplink (UL)) refers to the communication link from UEs to BSs.
In addition to conventional wireless multiple access communication systems, a new class of wireless multiple access communication systems employing BSs that cover small cell areas has emerged. These BSs can be installed in a home of a user and can provide indoor wireless coverage to UEs in or in geographic proximity to the home. Such personal miniature BS can be Femto BSs, Femto cells, Home Node B (HNB), Home eNode B (HeNB), or the like.
The BSs can operate according to restricted association, or closed subscriber group (CSG), methods whereby the owner of the home BS can determine which UEs are allowed to associate with the home BS. This is similar to, for example, 802.11 access points, wherein the wired equivalent privacy (WEP)/Wi-Fi protected access (WPA) key or explicit media access control (MAC) address provisioning can allow the owner of the access point to control access. Accordingly, UEs that are in geographic proximity to a BS, and have a radio link quality that would allow communication with the BS, could be prevented from such communication if the UE is not associated with the BS and/or within the subscriber group for the BS. The UEs can nonetheless cause interference to the BS when the UE transmits on the UL. Similarly, the UE is more susceptible to interference from the BS when the BS transmits on the DL to UEs with which the BS is associated. Accordingly, systems, apparatus and methods for interference management are desired.